Angioplasty and stenting of the large conductance vessels that supply the brain is a relatively new treatment that may be a viable alternative to carotid endarterectomy. Based on the extensive history of coronary artery stenting, it can be surmised that restenosis will be a key factor limiting the long-term success of carotid arterial stenting. The hemodynamic factors that influence restenosis, especially pulsatile pressure and flow, have received little scrutiny. We hypothesize that the degree of in-stent restenosis is related to pulsatility of pressure and flow. The following four specific aims will address this hypothesis: 1) To measure the degree of restenosis after carotid artery stenting and associated changes in pulsatile blood pressure and flow; 2) To predict with a patient-specific computational model the short and long-term changes in pulsatile pressure and flow after stenting; 3) To compare restenosis in rabbit iliac arteries that are subjected to high and low levels of pulsatile pressure and flow; 4) To compare remodeling factors in chronically stented vessels subjected to high and low levels of pulsatility. Dr. Quick is an engineer who has an extensive background in computational modeling of pulsatile hemodynamics in vascular beds. Funding is sought for a five-year training periodfor Dr. Quick to transition to a career in quantitative vascular biology. This project, addressing the interaction of hemodynamics and vascular biology, is a fundamentally new direction forDr. Quick, yet complements his expertise. Having studied the effect of vascular mechanical properties on oscillatory blood pressure and flow, he can now focus on the effect of oscillatory pressure and flow on vascular mechanical properties. This project represents a natural progression from theoretical tools to study the phenomena of vascular remodeling to the experimental tools to study the mechanisms of remodeling.